public class Calc {
    public static void main(String[] args) {
        int result = 0;
        if(args.length != 3){
            System.out.println("Usage:java Calc operato1operand(+ - * /)operator2");
        }
        else switch (args[1]){
            case "+":
                result = Integer.parseInt(args[0]) + Integer.parseInt(args[2]);
                break;
            case "-":
                result = Integer.parseInt(args[0]) - Integer.parseInt(args[2]);
                break;
            case "*":
                result = Integer.parseInt(args[0]) * Integer.parseInt(args[2]);
                break;
            case "/":
                result = Integer.parseInt(args[0]) / Integer.parseInt(args[2]);
                break;
            default:
                System.out.println("请输入正确的符号");
        }
        System.out.println(args[0] + "" + args[1] + "" + args[2] + "=" + result);
    }
}